In the manufacture of integrated circuits, semiconductor devices are formed on wafers of semiconductor material. Some of the processes used in the formation of semiconductor devices, such as chemical vapor deposition (CVD) processes, involve positioning the wafers in high temperature process chambers where the wafers are exposed to reactive gases to selectively form layers on the wafers.
The structures exposed to the high temperatures involved in semiconductor processing must be constructed from materials that can withstand the high temperatures. For example, robotic end-effectors, which are commonly used to transport wafers between high temperature process chambers, are often fabricated from quartz or ceramic materials. Such materials, although able to withstand the high temperatures involved in semiconductor processing, are typically brittle, and the structures of which they are made are often relatively fragile.
End-effectors, for example, are often broken during packaging, transportation and use. Many such end-effectors are formed of several plate-like layers which overlap one another and are bonded together. When the end-effectors are subjected to bending loads during packaging, transportation, or use, the end-effectors tend to fail at the edges or ends of the layers, where the cross-sectional area of the end-effector changes abruptly. Stress concentrations develop at these abrupt changes in cross-sectional area, causing the end-effectors to break at the stress concentrations when bending loads are applied.